Separating device comprising a cyclone separating device

ABSTRACT

The invention relates to a separating device for separating a multiphase medium, comprising a cyclone separating device ( 1 ) that provokes an at least partial distribution of at least two phases of said medium with the formation of a vortex flow for the medium. The invention is characterized in that each phase, which has a lower density compared to the respective other phase, is separated from said other phase and can be guided out of the separating device by means of a collecting device ( 35, 37 ).

The invention relates to a separating device for separating a multiphase medium, comprising a cyclone separating device which causes an at least partial distribution of at least two phases of this medium with the formation of a vortex flow for the medium.

Separating devices are prior art, see, for example, U.S. Pat. No. 6,129,775. These devices are used, for example, for separating media which in a liquid phase contain a second liquid phase (for example, aqueous phase/hydrocarbon phase) or a gaseous phase or suspended solids, or for media which in a gaseous phase contain a second gaseous phase and/or a liquid phase (for example, aqueous phase) and/or suspended solids.

Based on the prior art, the object of the invention is to provide a separating device which is characterized by especially favorable operating behavior when used to separate media with phases of different density.

This object is achieved according to the invention by a separating device having the features specified in claim 1 in its entirety.

Accordingly, an important feature of the invention consists in that each phase, which has a lower density than the respective other phase, is separated from this other phase and can be routed out of the separating device by means of a collecting device. Separation of the respective lighter phase from a liquid or gaseous phase especially advantageously allows hydrocarbon portions (oil) or gaseous components to be separated from an aqueous phase or media with gaseous phases to be separated into gases of different density.

In especially advantageous exemplary embodiments, the collecting device for the lower density phase has at least one discharge pipe which with at least one collection opening discharges in the cyclone separating device in a zone in which the lower density phase is separated by the vortex flow. Placing the mouth of a discharge pipe of the collecting device in a zone in which separation of the lighter phase is effected by means of the flow, which is both centrifugally active and which also runs axially, yields a suction action within the discharge pipe so that in the simplest construction the collecting device forms a suction device for the lighter phase so that an especially simple structure can be implemented for the entire device.

The suctioning-off of the lighter phase is made especially efficient when there is a widening which increases the inlet cross section of the collection opening at the end of the respective discharge pipe.

The widening can be especially advantageously formed by a conical intake funnel.

The arrangement here can be such that the outer edge of the intake funnel projects radially above the wall of the discharge pipe.

Alternatively, however, the arrangement can also be such that the intake funnel is formed within the wall thickness of the discharge pipe, which in this case has a correspondingly larger sufficient wall thickness. For an intake funnel integrated into the discharge pipe in this way, the advantage arises that the flow which runs upward on the outside of the pipe cannot be hampered by a funnel projecting above the outside of the pipe.

For a funnel integrated into the pipe wall, in the wall of the discharge pipe openings can be formed which lead into the interior of the intake funnel so that additional inlet cross sections for the lighter phase, which is to be exhausted, are formed.

In order to produce a coalescing effect in the flow which runs along the outside of the discharge pipe, there can be contouring on the outside of the wall of the discharge pipe. For this purpose, there can be grooves or ribs which run in the longitudinal direction or in helical lines. With respect to the coalescing action, contouring by bristles located on the outside of the pipe has proven especially effective, for example, by a round brush or spiral brush forming the contouring. Alternatively, there can also be an oleophobic coating on the outside of the pipe.

In especially advantageous exemplary embodiments, the cyclone separating device has a cyclone housing which defines a longitudinal axis with a housing inlet for inflow of the multiphase medium into a cyclone dome and a space which adjoins the dome along the longitudinal axis and which has the collecting device for the lower density phase and housing outlets for other phases, with the discharge pipe extending in the middle along the longitudinal axis within the space.

Especially advantageously, the arrangement here can be such that, proceeding from the cyclone dome, a flow body extends along the longitudinal axis as far as the end region of the discharge pipe. Here the end of the flow body facing the discharge pipe can have the shape of a cylindrical body, for example, with a diameter similar to or equal to the diameter of the discharge pipe. This cylindrical body stabilizes the flow of the lighter phase.

On the end of this cylindrical body, there can be a wedge-wire screen or a metal fabric which extends into the funnel-like widening of the discharge pipe in order to develop an additional coalescing action for the lighter phase.

The invention is detailed below using exemplary embodiments shown in the drawings.

FIG. 1 shows a longitudinal section of a cyclone separating device according to one exemplary embodiment of the separating device according to the invention;

FIG. 2 shows a partial longitudinal section of only the middle longitudinal section of a cyclone separating device of a modified exemplary embodiment, which partial section is shown broken away and enlarged relative to FIG. 1;

FIG. 3 shows another enlarged partial longitudinal section that shows a central section of the cyclone housing of a third exemplary embodiment;

FIG. 4 shows a partial longitudinal section of an exemplary embodiment which has been further modified, which section is similar to FIG. 2;

FIG. 5 shows a partial cross section according to the cutting line V-V of FIG. 4, and

FIG. 6 shows a partial longitudinal section of an exemplary embodiment which has been still further modified, which section is similar to FIG. 2.

In FIG. 1, a cyclone separating device is designated as a whole as 1, with its cyclone housing 3, with respect to a longitudinal axis 4 which runs vertically in FIG. 1, having an elongated shape. The cyclone housing 3, which is closed on the top end 5 and on the bottom end 7, adjoining the top end 5 forms a cyclone dome 9 into whose drum-like interior a multiphase medium can flow for phase separation via a housing inlet 11, where, in the manner which is conventional for cyclone separators, the housing inlet 11 is arranged such that the medium flows in tangentially with respect to the wall of the cyclone dome 9 and therefore a vortex flow is formed. The cylindrical cyclone dome 9 adjoins a cone part 13 with walls which converge downward, in which the vortex flow, with a flow velocity that is altered according to geometrical conditions, continues into an elongated cylindrical intermediate part 15 which is tapered relative to the cyclone dome 9 and whose lower end 17 is in turn adjoined by a cone part 19 with walls that converge downward which merges into a cylindrical bottom chamber 21 whose diameter corresponds to that of the cyclone dome 9 and which is closed on the bottom end 7. But it is also possible to choose the diameter of the cyclone dome 9 to be larger.

From the top end 5, proceeding from the cyclone dome 9, a flow body 23 extends downward in the form of a body of revolution which is coaxial to the longitudinal axis. In the example shown in FIG. 1, the flow body 23 in its free end region forms a guide body 25 in the form of a cone which runs within the cone part 13 and whose conicity is chosen such that the transition site between the cone part 13 and the housing part 15 has a certain cross-sectional narrowing, as a result of which the flow velocity of the partial flow which enters the cylindrical part 15 is uniformly accelerated up to the end of the cone and the centrifugal flow is directed. The centrifugal action of the axial flow causes separation of the phase that is “lighter” at the time within the cylindrical housing part 15.

In the zone of separation of the “lighter” phase, which zone is located within the cylindrical housing part 15, there is the collecting device for delivery of this phase, which will be detailed below. For the discharge of the conversely “heavier” phases from the bottom chamber 21, on its bottom is a housing outlet 27 with a pipe socket 29 which projects into the bottom chamber 21, which is coaxial to the axis 4, and from whose end a filter cartridge-like conical wedge-wire pipe screen filter element 31 extends beyond the cone part 19 into the cylindrical housing part 15. When the flow passes through the filter element 31, which runs from the outside to the inside, the solids are separated from the remaining denser liquid or gaseous phase so that solid-free liquid or solid-free gas emerges from the housing outlet 27. Solids which have been deposited on the outside of the filter element 31 and which sink or drop into the bottom chamber 21 are intermittently exhausted via another housing outlet 33. As FIG. 1 shows, this housing outlet 33 forms a discharge point which runs tangentially to the wall of the bottom chamber 21, similarly to the tangential entry point of the housing inlet 11 on the top end 5, but the discharge point at the housing outlet 33 works in the opposite direction thereto. Instead of a wedge-wire pipe screen filter element 31, there can also be a mesh fabric or the like.

The collecting device for the separated, respective “lighter” phase has a discharge pipe 35. The latter runs from the outside of the cyclone housing 3 through the housing outlet 27 of the bottom chamber 21 through the pipe socket 29 and the inner filter cavity of the filter element 31, which cavity is fluid-connected to the pipe socket, in the middle along the longitudinal axis 4 as far as the central region of the cylindrical housing part 15 where the zone of the separated “lighter” phase is located. The open end of the discharge pipe 35 thus forms the collection opening 37 for the outflow of the separated phase. For the geometry of the cyclone housing 3 shown in FIG. 1, where the vortex flow in the cylindrical housing part 15 moves axially downward until flow reversal takes place, and a secondary flow which rises along the outside of the discharge pipe 35 arises, a strong negative pressure prevails in the separation zone; that is, in the region of the collection opening 37 of the discharge pipe 35 and in the center of the vortex flow, as a result of which a strong suction action forms in the discharge pipe 35. At an axial velocity of from about 0.1 m/s to 0.4 m/s which is pointed downward in operation above the collection opening 37 in the cylindrical housing part 15 and for a secondary flow which rises along the discharge pipe 35 with an axial velocity of about 1 m/s, a flow velocity within the discharge pipe 35 downward can be established in the range of about 10 m/s. The discharge pipe 35 thus forms an effective exhaust apparatus for the lighter phase. In practical exemplary embodiments, the inside diameter of the discharge pipe 35 can be about 4 mm, with an inside diameter of the cylindrical housing part 15 of about 65 mm. This rising secondary flow is preferably formed from components of the light phase.

FIG. 2 shows an exemplary embodiment which has been modified relative thereto and which differs from FIG. 1 in that the flow body 23, instead of a shorter, end-side cone part 25, has an elongated cylindrical flow guide body 39. Moreover, on the end of the discharge pipe 35 is a widening which enlarges the inlet cross section of the collection opening 37 and which is formed by a conical intake funnel 41. The latter in the example of FIG. 2 is dimensioned such that the diameter on the outer funnel edge 43 which projects radially above the discharge pipe 35 is about six times the inside diameter of the discharge pipe 35. This execution ensures especially effective exhaust of the separated lower density phase.

FIG. 3 illustrates one version of the configuration of the discharge pipe 35 and its intake funnel 41. Instead of a fitted funnel with an edge which projects radially above the outside of the discharge pipe 35, the funnel 41 is integrated into the pipe wall 45 of the discharge pipe 35, which is made correspondingly thick-walled in this case. In this exemplary embodiment, in addition to the advantage of the inlet cross section of the discharge pipe 35, which cross section has been widened in the form of a funnel, there is the further advantage that there is no radially projecting funnel edge 43 around which the secondary flow which runs upward along the outside of the discharge pipe 35 must flow. As is shown in FIG. 3, in the pipe wall 45 of the discharge pipe 35, radial bores 47 are formed which lead into the interior of the funnel 41 and thus further enlarge the inlet cross section for the flow into the interior of the discharge pipe 35. The indicated funnel 41 can also be made from a metal fabric.

The outside of the discharge pipe 35 can be used to have a coalescing action on the secondary flow which is rising on it. For this purpose, the outside of the discharge pipe 35 can be provided with contouring or with an oleophobic coating for coalescing of oil, for example. FIGS. 4 and 5 illustrate an example in which for this purpose there are the bristles of a brush body 49 which surrounds the discharge pipe 35. The brush body 49 can be formed in this connection by a brush roll, by individual round brushes or spiral brushes. As suggested in FIG. 5 with oil droplets 51, coalescing takes place when the brush penetrates from the outside to the inside, and the outflow can take place within the gusset 53 (not all numbered).

It goes without saying that instead of contouring by means of the brush body 49 on the outside of the discharge pipe 35, there could also be grooves, or ribs, or the like.

FIG. 6 shows another example similar to the example of FIG. 2, aside from the fact that the free end of the flow guide body 39 is adjoined by a wedge-wire screen 55 which extends into the interior of the funnel 41. At a fineness of, for example, 500 μm, the screen 55 forms an additional coalescing zone within the exhaust zone for the phases of the respective lower density. All flows within the housing of the device move along a vortex flow which points in the same direction. In particular, the lighter phase which rises up opposite the other vortex flow within the housing of the device along the discharge pipe 35 has the same vortex direction so that no interference superpositions occur within the fluid flow. 

1. A separating device for separating a multiphase medium, comprising a cyclone separating device (1) which causes an at least partial distribution of at least two phases of this medium with the formation of a vortex flow for the medium, characterized in that each phase, which has a lower density than the respective other phase, is separated from this other phase and can be routed out of the separating device by means of a collecting device (35, 37).
 2. The separating device according to claim 1, characterized in that the collecting device has at least one discharge pipe (35) which with at least one collection opening (37) discharges in the cyclone separating device (1) in a zone in which the lower density phase is separated by the vortex flow.
 3. The separating device according to claim 1, characterized in that there is a widening (41) which increases the inlet cross section of the collection opening (37) at the end of the respective discharge pipe (35).
 4. The separating device according to claim 1, characterized in that the widening is formed by a conical intake funnel (41).
 5. The separating device according to claim 1, characterized in that the outer edge (43) of the intake funnel (41) projects radially above the wall (45) of the discharge pipe (35).
 6. The separating device according to claim 1, characterized in that the intake funnel (41) is formed within the wall thickness of the discharge pipe (35).
 7. The separating device according to claim 1, characterized in that in the wall (45) of the discharge pipe (35) openings (47) are formed which lead into the interior of the intake funnel (41.)
 8. The separating device according to claim 1, characterized in that there is contouring (49) on the outside of the wall (45) of the discharge pipe (35).
 9. The separating device according to claim 1, characterized in that the contouring is formed by a round brush (49) or spiral brush.
 10. The separating device according to claim 1, characterized in that the cyclone separating device (1) has a cyclone housing (3) which defines a longitudinal axis (4) with a housing inlet (11) for inflow of the multiphase medium into a cyclone dome (9) and a space which adjoins the dome (9) along the longitudinal axis (4) and which has the collecting device (35, 37) for the lower density phase as well as housing outlets (27, 33) for other phases, and that the discharge pipe (35) extends in the middle along the longitudinal axis (4) within the space.
 11. The separating device according to claim 1, characterized in that proceeding from the cyclone dome (9), a flow body (23, 29) extends along the longitudinal axis (4) as far as the end region of the discharge pipe (35).
 12. The separating device according to claim 1, characterized in that on the end of the flow body (39), there is a wedge-wire screen (55) which extends into the funnel-like widening (41) of the discharge pipe (35). 